Mistakes

Definition

A mistake is a special kind of error , when the operator's violation of an operational rule is intentional.

A mistakes is a conscious error, when the operators' goals are inappropriate for the situation. It is an error in intention

Example

If I misunderstood the meaning of the oil-pressure warning light in my car, and thought it was the tire-pressure monitor, no matter how carefully I added air to my tires, it would not fix the issue with my oil pressure. This would be a mistake, since the goal that I was attempting to accomplish was inappropriate for the situation, even though I made no errors in executing my plan.

Sources of mistakes

Mistakes are made when operators have goals that are inappropriate for the current problem or task; even if they take the right steps to complete their goals, the steps will result in an error. Often (though not exclusively) they arise when an operator has incomplete or incorrect information about the task, and develops a mental model that doesn’t match how the interface actually works. (adapted from: http://www.nngroup.com/articles/slips/ )

Prevention

To prevent mistakes, we need to make inform the operators about the implications of infringing the operational rules.

Implementation

The challenge about mistake prevention is to figure out the the operators are about to infringe the rules, before the actually do it.

Methods

The recommended architecture ... includes special gates, used to prompt the operators about rule violation, enabling them to learn about the risks and then either confirm or regret.